In recent manufacturing industries, various adhesives and tape-type adhesive materials have been extensively used. Meanwhile, many countries have strengthened environmental regulations on such industrial products used particularly in electronic products, vehicles, and the like. Therefore, reducing the amount of volatile organic compounds (VOC) and odorous pollutions during the manufacturing of such products has been an outstanding issue in the vehicle industry. Furthermore, there have been continuous needs for developing a high-functional tape having superior tackiness and flame retardancy.
Vehicle manufacturers have made efforts to reduce vehicle weight, and the materials used in vehicle manufacturing have been extended to include non-ferrous metals. Accordingly, a demand for adhesives and tackifying tapes has also increased. For example, a headliner of a vehicle, which is apart for reducing a body weight in a vehicle, is formed of a combination of materials including an expandable resin.
However, when such materials are used, the body strength of a vehicle may be deteriorated, and further deformation of an intrinsic shape of a vehicle may occur during operation and storage. Accordingly, metal brackets are often attached to a headliner to fix the headliner. In addition, materials for parts of a vehicle may have environment-friendly properties from development steps to meet environmental requirements of the vehicle industry while having high tackifying property and flame retardancy.
Among numerous vehicle parts, a headliner may be made of expandable resin, and a shape of the headliner may be bent or deformed during operation, transportation, and storage. To prevent such damages, a metal bracket is often attached to the headliner. When the bracket is not sufficient to fix the headliner, a driver or any passengers may be significantly threatened during an accident. Thus, securely attached brackets to the headliner are critical items in manufacturing of the vehicle. When such a headliner structure with the brackets attached is included, the conventional manufacturing method may not be efficient because the weight of the vehicle increases and the productivity of manufacturing decrease.
Alternatively, a tape that fixes the headliner with the bracket for the exclusive use of vehicles may be one of the most suitable solutions for the aforementioned problems. Thus, such an adhesive or a tape may be required to exhibit high attachment strength with a material having a rough surface of the headliner.
In recent developments of adhesive materials, an acryl-based aqueous pressure-sensitive adhesive composition has been developed. However, such acryl-based aqueous pressure-sensitive adhesive composition has limitations. For example, phenol may be thermally decomposed and a benzene derivative may be generated during a heat reaction due to a terpene phenol resin used in the manufacturing of such adhesives, causing harmful contaminants to be discharged. In other example, a method of manufacturing a tape coated with an acryl-based attaching agent, and a tackifying tape to which ethyl acetate and acetone have been developed. However, problems in maintaining flame retardancy and high attachment strength may occur.